Tougher sentences for some firearms offences, a gun amnesty and the introduction of anti-social behaviour orders were among the amendments to the Criminal Justice Bill announced by Minister for Justice Michael McDowell.

He said he would also introduce an offence of contributing to, or participating in, the activity of a criminal organisation. This would carry a five-year sentence.

The Minister said mandatory minimum sentences of between five and 10 years would be introduced for certain firearms offences.

These would include possession of a firearm in suspicious circumstances; possession of a firearm with criminal intent; possession of a firearm with intent to endanger life or cause serious injury to property; possession of a firearm while hijacking a vehicle, and use or production of a firearm to resist arrest.

"In addition, I am also introducing new offences concerning the modification of firearms such as 'sawing-off' a shotgun and increasing fines and penalties generally for offences under the firearms acts."

Mr McDowell said he would introduce a statutory basis for an amnesty during which firearms might be surrendered to the Garda before new penalties and minimum mandatory sentences were introduced.

"This will enable those in possession of firearms who are not in compliance with the legal requirements to regularise their position, and thus enable the Garda Síochána to concentrate on more serious offenders.

"During the amnesty period, persons who surrender weapons will not be prosecuted for the simple illegal possessing of the weapon. However, surrendered weapons will be forensically tested and, where found to have been used in a crime, the weapon and the forensic evidence will be admissible in any proceedings subsequently brought."

On anti-social behaviour orders, Mr McDowell said there would be two distinct sets of arrangements, one for children between 12 and 18 years and the other for adults.

"The application for an order will be a last resort after other options have been tried and have not been seen to work. In both cases only a senior garda may apply for an order."

Other proposals, he said, would include measures to protect staff at A&E departments in hospitals and other emergency workers from assaults.

Fine Gael spokesman Jim O'Keeffe said: "The way in which the Minister has handled the Bill means that very necessary changes, which were proposed nearly two years ago, are still in legislative limbo." In the meantime, a lot of ground in the battle against crime had been lost.

He added that it would have been better to have dealt with firearms in a separate Bill.

Labour spokesman Joe Costello said it was two years since the heads of the Criminal Justice Bill were published.

"The Bill appeared in July 2004; it was debated in the Dáil in January 2005. Now 15 months later, the Minister has published over 200 amendments, increasing the size of the Bill by six times its original size. The whole thing is a legislative shambles."

John Gormley of the Green Party said it was wholly inappropriate that such a wide range of issues be dealt with in one piece of legislation.

The Oireachtas justice committee will now consider the amendments.